Coil spring



' A. L. VARGHA COIL SPRING Filed .Juge V14 1929 Patented June 14, 1932 UNITED STATES PATENT OFFICE ANDREW 'LOUIS VARGHA, OF DETROIT, MICHIGAN, ASSIGNOR TO GENERAL MOTORS CORPORATION, OF DETROIT, MICHIGAN', A CORPORATION OF DELAWARE COIL SPRING Application filed J'une 14, 1929.

When a helical coil spring of the ordinary construction, i. e., one which is made of spring wire of uniform shape in cross-section and uniform cross-sectional area, Wound into a coil. of uniform diameter and uniform pitch, is acted upon by a periodic force of a certain frequency, it will vibrate freely in resonance With the periodic force. This vibration of a spring at its natural frequency is what is commonly known as surge Surge in springs, and particularly in the valve springs of poppet valve engines, is a very undesirable characteristic. In general, Surg/e7 causes forces of undesirable strength and frequency to be imposed on a spring and is likely to cause breaking of the spring and associated parts of the mechanism in which the spring is incorporated. Surge in the valve springs of poppet valve engines is further undesirable on account of its effect upon the opening and closing movements of the valves.

This invention relates to helical coil springs and resides in the provision of a helical coil spring made of spring wire which is deformed longitudinally, or transversely, or both, so that the spring is incapable of vibrating in resonance with a periodic force and, therefore, incapable of surging For a better understanding of the nature and the objects of the present invention, reference is made to the following specification in which are described the preferred embodi-l ments of my invention, which are illustrated in the accompanying drawing.

In the accompanying drawing:

Figure 1 is a perspective View of a length of spring Wire from which a spring in which is embodied my invent-ion may be made.

Figure 2 is a perspective view of a helical coil spring made from a length of wire similar to that shown in Figure 1.

Figure 3 is an end elevation of the coil spring shown in Figure 2.

Figure 4 is a perspective view of a length of spring wire of modified form from which a spring in which is embodied my invention may be made.

Figure 5 is an enlarged section taken on the line 5-5 of Figure 4.

Serial No. 370,819.

In the embodiment of my invention, which is illustrated in Figures 1 to 3 of the drawing, the spring is made of a length of spring Wire 10 by first deforming it so that it is of a more or less sinuous shape as shown in Figure 1. The deformation may be in one plane only or in a plurality of planes, as illustrated in the drawing. After being so deformed, the wire is Wound by any usual or suitable means into a coil 11, as shown in Figures 2 and 3 of the drawing.

In the embodiment of my invention, which is illustrated in Figures 4 and 5 of the drawing, the spring is made of a length of spring wire 12, by first deforming it so as to provide in its length portions of different shape in cross section. In the embodiment shown in Figures 4 and 5, the wire is so deformed as to provide therein a series of round portions 13 connected by fiat portions-the fiat portion 14 at one end of each round portion being located in a' plane which is at a right angle to the plane in which the fiat portion 15 at the opposite end thereof is located. After being so deformed, the wire is wound into a coil, similar to that shown in Figures 2 and 3 of the drawing.

Although I have shown land described preferred embodiments of my invention, it is to be understood that this has been done merely by way of example and not by way of limitation, and that the scope of my invention is to be limited only by the appended claims.

I claim:

1. A coil spring of wire of sinuous shape in which the sinuosities are located in al plurality of planes.

2. A coil spring of wire having alternate fiat and round portions, and in which the flat portions are located in a plurality of planes.

3. For use in mechanisms which include a spring which is subjected to the action of a periodic force or periodic forces during the normal operation of the mechanism, a coil spring which is made of wire of sinuous shape.

4. A coil spring of deformed Wire in which the deformations are located in a plurality of planes.

5. For use 1n mechanisms which'include a spring which is subjected to the action of a periodic forcer periodic forces during the normal o eration of the mechanism, a, coil spring o wire havingaiternate round and Hat portions.

In testimony whereoI ax my signature.

ANDREW LOUIS VARGHA. 

